U.S. Steel, CarbonFree to explore 50K-mtpy mineralization project

Sources: United States Steel Corp., Pittsburgh; CarbonFree Chemical Holdings LLC, San Antonio, Texas; CMCM staff  

Under a non-binding memorandum of understanding, U.S. Steel and CarbonFree will discuss pursuit of a carbon dioxide emissions capture and mineralization commercial venture at the former company’s heritage Gary Works. If reached, potentially by year end, a definitive agreement could lead to the 2025 startup of a CarbonFree SkyCycle installation at the Indiana mill, whose annual raw steel capacity hovers 7.5 million tons. Equipment would be scaled to convert up to 50,000 metric tons of Gary Works CO₂ per year to precipitated calcium carbonate with hydrochloric acid co-product. 

CarbonFree has proved the SkyCycle process at a cement plant, capturing carbon dioxide from the exhaust and sequestering it in mineralized calcium carbonate. The finely graded mineral suits the global specialty chemicals market, where end uses include paper, plastic, ceramic, paint, adhesive, sealant and rubber production.

“As we aim to widely introduce and scale our technology to industrial facilities across the globe, we are thrilled for the possibility of bringing SkyCycle carbon capture capabilities to one of the largest integrated mills in North America,” says CarbonFree CEO Martin Keighley. “We are committed to working with U.S. Steel to achieve their sustainability goals and to further our mission of helping enable the world’s transition to net zero carbon emissions.”

“We are eager to enter the next phase of discussions with CarbonFree to explore the possibility of meaningful CO₂emission reductions in our operations in a capital efficient manner,” adds U.S. Steel Senior Vice President – Chief Strategy & Sustainability Officer Richard Fruehauf. “Working with CarbonFree could be a meaningful step in our efforts to decarbonize the Gary Works plant while developing technology and knowhow that we could apply to other facilities. These potential collaborations are critical as we continue our mission of providing profitable steel solutions for people and planet.”